1. Field of the Invention
The present invention relates to a solar radiation detecting device for detecting the sunlight coming into the passenger compartment of an automobile and an automobile air-conditioner using such solar radiation detecting means.
2. Description of the Prior Art
One known solar radiating condition detecting device is disclosed in Japanese Patent Laid-open Publication No. 62-73108, for example. The detecting device includes a base in the form of a truncated quadrilateral pyramid disposed on the upper surface of an instrument panel, and solar radiation sensors disposed on three or four sides, respectively, of the truncated quadrilateral pyramidal base for detecting the incident direction of the sunlight and other solar radiating conditions of the automobile based on outputs from the respective sensors.
With this mounting structure of the solar radiation sensors, the known detecting device is unable to perform a sufficient detection of the direction, altitude and intensity of the incident sunlight among other solar radiating conditions. This is because due to the directivity of the respective solar radiation sensors, the output from one solar radiation sensor can be compensated by another solar radiation sensor in terms of detection of the incident direction of the sunlight, however, such compensation of outputs is difficult to obtain when the incident altitude and the incident intensity of the sunlight are detected.
Furthermore, the position of the sunlight incident upon an occupant of the automobile via the instrument panel changes with the altitude of the sun. It is therefore desired that the solar radiating conditions are detected accurately and, based on the thus detected solar radiation conditions, the automobile air-conditioner is controlled to adjust the direction of discharged air appropriately.